"""
函数定义声明，需要动物类型和名字
"""
def describe_pet(pet_name, animal_type = 'dog'):
    """显示宠物信息"""
    print("\nI have a " + animal_type + ".")
    print("My " + animal_type + "'s name is " + pet_name.title() + ".")

# describe_pet(pet_name='willie')
describe_pet('willie')